The invention relates to a system by which a chain of interconnected reclosable plastic bags equipped with interlocking fastener strip rib and groove profiles ("zippers") are individually opened, filled, closed, and separated from the chain for packaging.
A zipper lock plastic bag of the type described, for example, in U.S. Pat. No. 3,198,228 has closed bottom and side edges and a reclosable upper end mouth with interlocking fastener strip rib and groove profiles running across inner facing surfaces of the mouth. The nature of manufacture and operation of the reclosable plastic bags presents altogether different handling problems than those presented by bags arranged for heat seal closing. For instance, reclosable zipper lock bags are typically closed at their mouth ends during the manufacture process in order to allow for proper interfitting of the rib and groove members and exit the manufacturing site in that closed condition. The bag mouths must be opened at a loading site to permit filling and then closed again for packaging.
In recent times, an automated machine was devised, as disclosed, for example, in U.S. Pat. No. 4,490,959, for transporting, opening, filling, closing, and separately discharging reclosable zipper lock plastic bags sequentially one at a time in a fully automated manner. The bags passed through the machine are interconnected with one another in a chain. While this machine is ideal for users having relatively high production packaging requirements, there is still a need for a more economical zipper bag filling machine which is reliable and convenient, but which better suits the cost expectations and demands of relatively smaller or speciality packagers with low or intermittent production.
The present invention concerns a method and means for filling zipper lock plastic bags which directly satisfies the cost, production, and operational requirements of the low or intermittent production packager and affords reliability and convenience, making rapid filling of zipper lock plastic bags readily available to this type of packager.